Two former Parramatta Eels players are accused of harbouring semi-automatic weapons and possessing more than half-a-million dollars in cash after dramatic arrests in Sydney's Centennial Park yesterday.

'No evidence' of terrorism links in WA

Premier Colin Barnett says there is no evidence of terrorists operating in Western Australia, but people would continue to see a tighter level of security.

His comments came after pre-dawn raids across Sydney and Brisbane on Thursday, in which 15 people were detained and one person was charged with terrorism offences.

Asked about the operation but speaking more generally, Mr Barnett said "to this point" there had been no evidence of any terrorism links to WA but said there was no doubt there was a section of very radical people within Australia.

"It's a serious threat and there's a real fear that there may be some sort of terrorist act somewhere in Australia, but no evidence of any of these people operating within this state," he told Fairfax radio on Thursday.

Mr Barnett told Fairfax radio that people should feel safe in Australia because authorities were taking pre-emptive action.

"Security measures are being checked and people can probably expect to see a tighter level of security," he said.